Advertisements
Advertisements
Question
Write the electronic configuration of K and Ne.
Advertisements
Solution
| Element | Electronic configuration |
| K | 2,8,8,1 |
| Ne | 2,8 |
APPEARS IN
RELATED QUESTIONS
Given below are some elements of the modern periodic table. Atomic number of the element is given in parentheses.
A(4), B(9), C(14), D(19), E(20)
(a) Select the element that has one electron in the outermost shell. Also, write the electronic configuration of this element.
(b) Which two elements amongst these belong to the same group? Give reasons for your answer.
(c) Which two elements amongst these belong to the same period? Which one of the two has bigger atomic radius?
Two elements ‘A’ and ‘B’ belong to the 3rd period of Modern periodic table and are in group 2 and 13, respectively. Compare their following characteristics in tabular form:-
(a) Number of electrons in their atoms
(b) Size of their atoms
(c) Their tendencies to lose electrons
(d) The formula of their oxides
(e) Their metallic character
(f) The formula of their chlorides
Calculate the number of gram atoms in 4.6 grams of sodium (Na = 23)
The atomic radii of three elements X, Y and Z of a period of the periodic table are 186 pm; 104 pm and 143 pm respectively. Giving a reason, arrange these elements in the increasing order of atomic numbers in the period.
How does the electropositive character of elements change on going down in a group of the periodic table?
How do atomic structures (electron arrangements) change in a period with increase in atomic numbers from left to right?
How does the size of atoms (atomic size) generally vary in going from left to right in a period of the periodic table? Why does it vary this way?
For each of the following triads, name the element with the characteristics specified below:
| Elements | Least atomic radius | Chemically least reactive |
| (i) F, Cl, Br (ii) Li, Na, K |
.................... .................... |
.................... .................... |
How does the atomic size vary on going down from top to bottom in a group of the periodic table? Why does it vary this way?
In which part of a group would you separately expect the elements to have the greatest metallic character
Where would you locate the element with electronic configuration 2, 8 in the modern periodic table?
What do you understand by periodicity?
Which element has:
twice as many electrons in its second shell as in its first shell?
Name the element in period 3 which does not form oxide.
name the elements in period 1.
What is the common feature of the electronic configuration of the elements at the end of period 2, and period 3?
An element 'M' has atomic number 11.
(a) Write its electronic configuration.
(b) State the group to which 'M' belongs.
(c) Is 'M' a metal or a non-metal.
(d) Write the formula of its chloride.
F, Cl and Br are the elements each having seven valence electrons. Which of these (i) has the largest atomic radius, (ii) is most reactive? Justify your answer stating reason for each.
Fill in the blank
There are ______ groups and ______ periods in the modern form of periodic table.
How could the atomic radius of a noble gas be compared with the other elements in a period?
'In a group, the atomic radii increase with increasing period number', explain this statement and justify it with reference to group 17.
Select the correct answer
Number of shells in potassium are
The following questions refer to the Periodic Table.
What is the common feature of the electronic configurations of the elements in group 7?
An element Z has atomic number 16. Answer the following
(a) State the period and group to which Z belongs
(b) Is Z a metal or a non-metal?
(c) State the formula between Z and hydrogen.
(d) what kind of a compund is this?
Choose the most appropriate answer from the following list of oxides which fit the description.
An oxide which dissolves in water forming an acid.
Arrange the following as per instruction given in the bracket.
Cs, Na, Li, K, Rb (increasing metallic character)
Arrange the following as per instruction given in the bracket.
K, Pb, Ca, Zn (increasing reactivity)
Arrange the following in order of increasing radii:
Mg2+, Mg, Mg+
Name and state the following with reference to the elements of the first three periods of the periodic table.
Valency of elements in Group 14 and 15.
An element A has 2 electrons in its fourth shell. State:
position in the periodic table
The electronic configuration of an element is 2, 8, 4. State it:
name and write its one physical property.
Based on the group valency of element write the molecular formula of the following compound giving justification:
Compound formed when an element A of group 2 combines with an element B of group seventeen.
Name the period which is the shortest period of the periodic table.
Name or state following with reference to the element of the first three periods of the periodic table.
A non-metal in period 2 having electronic configuration 2, 6.
Name or state following with reference to the element of the first three periods of the periodic table.
The formula of the hydroxide of the element having electronic configuration 2, 8, 2.
Name or state following with reference to the element of the first three periods of the periodic table.
A non-metal in period 2 which is tetravalent.
Select the correct answer from the options given below.
Is the group number of the element whose atomic number is 4.
Fill in the blanks from the words A to F given below’.
A: Decreases
B: Increases
C: Remains same
D: Increases by one
E: Electropositive
F: Electronegative
Across a period from left to right in the Modern Periodic Table.
No. of electron shells _________; No. of valence electrons __________: Electronegativity increases Character of elements changes from electropositive to ________.
